I went through a bit of a flood on the road a while back and just afterwards the high note horn stopped working. The low note is still OK.
I took it off and checked it direct on the battery and it sort of half worked if I beat it. I assumed the water had done the damage, but after looking through various posts here, it seems like they aren't too reliable.
I should have taken it back to the dealer before December, but now the guarantee has expired. I like the sound it makes, that one on e-bay looks pretty feeble as it's only a disc type, like on mopeds. The original is a trumpet type, although still electromechanical.